According to a report by Tech Crunch, popular cross platform instant messaging app WhatsApp, could possibly be acquired by Facebook, so reveals a source with knowledge of the possible deal.

While at this point there seems to be very few details about the matter available, considering Facebook’s interest in connecting with its users through mobile devices, it is quite possibly the next step for the social network and something Mark Zuckerberg voiced would be “crucial” for Facebook to reach its “next billion” batch of active monthly users.

According to the report Zuckerberg told BusinessWeek in an interview in early October that “The big thing is obviously going to be mobile. There are 5 billion people in the world who have phones. There are actually already 600 million people using Facebook on phones, so that’s growing really quickly. And as more phones become smartphones, it’s just this massive opportunity.”

WhatsApp itself, that delivers text messages as well as images and audio and video messages, has an extensive global reach currently being used in over one hundred countries covering 750 mobile networks, iOS, Android, BlackBerry, Nokia S40, Symbian and Windows Phone platforms.

While people were questioning the rationale behind Facebook’s $1Billion purchase of Instagram earlier this year, WhatsApp’s value is indeed much easier to understand. It is a cross platform messenger that has become the first install on any new phone for many people.

While it looks like a great investment for Facebook, we are in two minds whether we want Facebook to control another aspect of our online and mobile life.